Window air conditioner



FIG. 1 is a front view of a window air conditioner showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a right side elevational view thereof; and,

FIG. 4 is a left side elevational view thereof.

The portions of the article not shown in the drawing or described in the specification form no part of the claimed design. 

The ornamental design for a window air conditioner, as shown and described. 